SIX MONTHS ago, Warwick Steele was dealing with the awful reality that his life would soon be over.

The 64-year-old TV engineer had advanced skin cancer and had been given just months to live. Now, after being treated with pembrolizumab, the tumours that had spread to his lungs are all but gone.

Although doctors cannot be sure it was the pioneering new drug that led to the “miraculous” outcome for Warwick, they have NO other explanation.

And after the remarkable results from an early-stage trial of the drug, hopes are growing that medics have taken a massive step forward in the battle to find a cure for cancer.

Warwick’s consultant, Dr David Chao, said: “We cannot say for certain that he’s been cured but he is doing very well. He was aware that without an effective treatment, his survival prospects were not good – maybe months.”

Pembrolizumab is the latest in a new generation of treatments that prevent cancers shielding themselves from the immune system.

It was tested on melanoma – the most dangerous form of skin cancer – because the prospects for patients with advanced forms of this disease are so bleak.

Just under 70 per cent of the 411 taking part in the trial were alive a year after starting treatment.

Currently, one-year survival rates for untreated patients diagnosed with advanced stage four melanoma are just 10 per cent for men and 35 per cent for women.

Dr Chao, from the Royal Free Hampstead NHS Trust in London, added: “Pembrolizumab looks like it has potential to be a paradigm shift for cancer therapy and is helping to establish immunotherapy as one of the most exciting and promising treatments.

“This is one of several new drugs of this type being produced. What these early trials are showing is that they are fulfilling their promise ridiculously fast. Some of these results are astonishing; almost jaw-dropping. And these drugs may be applicable to many different cancer types, including ones that are hard to treat, such as lung cancer.

“Can we dream about curing some of our patients with very advanced cancer? Once we get the immune system attacking the cancer, can it act independently to keep the cancer under control?

“We don’t have all the answers yet but that’s what we’re looking at.

“The major problem with cancer, even with successful treatments in the past, is that the cancers have adapted to our treatments and they come back. I think one of the hopes of immunotherapy is that, by harnessing the power of the immune system, the immune system will adapt to the cancer and, therefore, will be able to keep it under control, possibly for a very long time, possibly leading to a cure but I think only time will tell.”

Warwick, from Ruislip, London, had six months of treatment with pembrolizumab, which is injected into the bloodstream.

It is a synthetic antibody that blocks a biological pathway called programmed cell death 1 (PD-1), which cancers activate to suppress the immune system.

In healthy individuals, PD-1 is part of the process that applies a “brake” to the immune system and prevents it running out of control.

Without the brake, there is a risk of a harmful inflammatory reaction – a potential serious side-effect of the new drugs. Pembrolizumab was generally well tolerated by the trial patients. Results from the trial were presented to the American Society of Clinical Oncology in Chicago.

Clinicians do not yet know the true extent of how pembrolizumab might affect survival.

But after 18 months, 62 per cent of patients were still alive and undergoing treatment.

In addition, around 80 per cent of patients responded to the drug.

A total of 72 per cent experienced tumour shrinkage.

Pembrolizumab’s manufacturers, Merck Sharp & Dohme, are set to apply for a European licence to market the drug within months.

Each year, around 13,300 people in the UK are diagnosed with melanoma – more than a third aged under 55.

Gillian Nuttall, of Melanoma UK, said: “The pembrolizumab results are exciting and could represent a turning point for patients affected by advanced melanoma.”